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Influence of nanoscale regions on Raman spectra of complex perovskites

E. A. Rogacheva
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Abstract

New approach on interpretation and processing of Raman spectra of complex perovskites is suggested. Raman spectra of $PbMg_{1/3}Nb_{2/3}O_{3}$ and $% PbSc_{1/2}Ta_{1/2}O_{3}$ are successfully described on the basis of the phonon-confinement model and validity of the method is demonstrated on good agreement of experimentally obtained and computer simulated spectra of another complex perovskite, $BaMg_{1/3}Ta_{2/3}O_{3}$. The study showed that the size of nanoscale regions is a kind of an inborn characteristic of the sample and is not temperature dependent. For $PbSc_{1/2}Ta_{1/2}O_{3}$, two special temperature points, approximately 400 K and 600 K are found from the analysis of the temperature behaviour of obtained mode parameters.

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E. A. Rogacheva. 1999-07-23. Influence of nanoscale regions on Raman spectra of complex perovskites. https://arxiv.org/abs/cond-mat/9907366

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